Glass container inspection machine

ABSTRACT

Containers are diverted from a conveyor onto a base where each container is rolled into an inspection station defined by three rollers. A side belt rolls the containers against a rail and one of the three rollers projects beyond the rail at said inspection station. The other two rollers are independently mounted on oscillating arms which move the side belts into contact with the container to rotate it at said inspection station. An improved inspection head is also disclosed, and the method of fabricating said head whereby the machine can be set-up for inspecting containers of various configuration with a minimum downtime of the machine, all of the light emitters and sensors being frozen in a block in a head for a particular container configuration.

United States Patent [191 Krenmayr 1 1 Nov. 19, 1974 GLASS CONTAINERINSPECTION MACHINE [75] Inventor: Willy Krenmayr,Jona, Switzerland I[73] Assignee: Emhart Zurich S.A., Zurich,

[30] Foreign Application Priority Data Jan. 19, 1972 Switzerland 761/72[52] US. Cl 209/ll1.7, 198/283, 198/19, 250/223 B, 356/198, 356/240 [51]Int. Cl C10g 13/02 [58] Field of Search 198/19, 31 R, 31 AA, 34,

GEN.

2/1969 Kulig 209/111.7 8/1972 Nichols et a1 198/283 PrimaryExaminer-Richard A. Schacher Assistant Examiner-Joseph E. ValenzaAttorney, Agent, or FirmMcCormick, Paulding & Huber [57] ABSTRACTContainers are diverted from a conveyor onto a base where each containeris rolled into an inspection station defined by three rollers. A sidebelt rolls the containers against a rail and one of the three rollersprojects beyond the rail at said inspection station. The other tworollers are independently mounted on oscillating arms which move theside belts into contact with the container to rotate it at saidinspection station. An improved inspection head is also disclosed, andthe method of fabricating said head whereby the machine can be set-upfor inspecting containers of various configuration with a minimumdowntime of the machine, all of the light emitters and sensors beingfrozen in a block in a head for a particular container configuration.

25 Claims, 7 Drawing Figures PATENIE' PIIJY 1 9mm 3.848.742 SHEET 20F 5FIG. 2

pmmwzavismn v 3, 4 sum says FIG. 3

, PATENTE AUV I 9|974 3 4 742 SHEH' I 0F 5 S TIME I DELAY ONE ONE 204200 START TWO 'DLER J 2 STAGE TWO STAGE ARM COUNTER I 2OI POSITIONSENSOR BACKUP 206 WHEEL A DRIVE PULSE ROTATION & BRAKE GEN. COUNTER 203POSITION \J SENSOR IDLER 202 ARM \J r COUNTER 2 OUTFEED EEE CONVEYORCOUNTER 220 2Is WW WW ,w I I f 2 l2 U m UNIT II HI UN'T SIGNAL MEMORYPATENIE MHQIQM 3,848,742 SHEET 50? 5 GLASS CONTAINER INSPECTION MACHINEBACKGROUND OF THE INVENTION Glass containers such as bottles, flasks orjars for the food industries or pharmaceutical industry, generally areproduced in automated installations or plants. The production rates ofsuch installations are very high. For example, containers with a unitweight of 100 g are produced at rates of up to 200 units per minutewhile containers with a unit weight of 900 g are produced at rates of upto 65 units per minute. To assure that contours or shapes, volumes(capacity) and other features of the containers are in accordance withproduct specifications including final use requirements, such assuitability for automatic bottling (filling and closing) which mayrequire pressure sealing caps, crown corks or stoppers, a very rigidinspection of such critical features is required. Furthermore, thecontainers must be checked for absence of defects such as cracks, mostimportantly at the neck and bottom portion of the containers becausesuch defects would increase the breakage hazard or render closing of thecontainers impossible. The term crack, here, is intended to includevarious types of crizzles, splits, checks, fissures, blisters, spikes,jaggers and other defects inside the glass, whether they extend to aglass surface or not, capable of being spotted by deflection of lightbeams.

Both defects of contours or dimension and cracktype defects at the neckor bottom portions of the containers appear at random. Therefore,spot-checking or random-checking does not provide a sufficient qualitycontrol and each container produced msut be examined individually. Forthis purpose, commercial container producing installations of the typementioned above generally include inspection lines for checking thecontainers produced.

According to conventional practice, cracks at the neck or bottomportions of glass containers are detected by optical means. For example,in a typical crack-checking apparatus, each container is rotated aroundits vertical axis at least once, while at least one beam is directed atthe article under inspection. For

' crack detection, the light emanating or being reflected from saidcontainer under predetermined angles is surveyed. This method works onthe principle that cracks of the type mentioned above in vitreoussubstances are capable of forming an optical interface or boundarytherein. Such a boundary will totally reflect a light beam with an angleof incidence greater than the critical or limiting angle of totalreflection. This result is utilized to trigger a sensor for eitheraccepting or rejecting that container.

In U.S. Pat. No. 3,533,704, issued in 1970 to the inventor herein, aninspection method is disclosed for taking advantage of this principle.Another approach is disclosed in U.S. Pat. No. 3,639,067 issued in 1972to Stephens.

Most cracks are caused by stresses or tensions which result from initialcooling of the glass. While annealing may alleviate stresses it does notnecessarily eliminate all cracks. The general direction of such crackswill usually be from the outer glass surface toward the inner surface ofthe glass container, that is predominantly in a radial direction. Inorder to detect substantially all such cracks regardless of theirposition and direction,

a crack-checking apparatus generally includes several light emitters andseveral light sensors. Since the totally reflected light bundles have awidth and, concomitantly an intensity, which increases as the angle ofimpact approaches the critical or limiting angle of total reflection,emission of the light bundle and the sensor or detector preferably arearranged such that the angle of the incident light approaches thelimiting angle of total reflection. Further, in order to detect or sensetotally reflected light, the incident light bundle and the lightreceiving part or sensor of the light detector should be in the sameplane and be perpendicularly oriented with respect to the plane definedby the crack. It should be noted that the foregoing comments applyparticularly to my prior U.S. Pat. No. 3,533,704 referred to above.Others have been successful in orienting light emitters and sensors inother ways for inspecting containers of various configurations. Forexample, the Stephens U.S. Pat. No. 3,639,067 illustrates a slightlydifferent approach to the concept of inspecting glassware by opticalmeans.

Whichever approach one chooses to follow, the technical problem is toarrange a plurality of light emitters or light sources, suitable forgenerating such light beams or bundles, and a plurality of coordinatedlight sensors or detectors under mutual angles which are functionallydependent upon the angles of reflection and refraction, and theirpositions will depend upon shape, contour and dimension of thecontainers to be tested. Mechanically, such an arrangement must be quitestable because the machines, and checking installations, are subjectedto strong and continuous vibration, and also because it may happen inhigh speed production and its concurrent high conveying velocities thata container rebounds somewhere from the conveying line and hits thesupport of the testing devices or the testing devices proper. On theother hand, the arrangement or support should allow quick andreproducible setting or resetting of the testing devices so that upon achange of production from one size or type of container to another,readjustment is possible within a reasonably short time. The sametesting apparatus can sometimes be used for continuously checkingcontainers of various vertical heights when the neck or finish issimilar to some other container configuration.

Inspection apparatus of various types are known and have, for example,been disclosed in U.S. Pat. No. 2,902,151 issued to Miles in 1959; No.3,101,848 issued to Uhlig in 1963 and No. 3,249,224 also issued to Uhligin 1963. These prior art machines do not show or suggest anystandardized inspection head design, but instead generally include anumber of vertical columns or rods interconnected by means of horizontalrails or cross bars with the optical testing devices mounted either onthe rods or the rails by means of bars and pivotable brackets or knucklejoints. Such arrangements can be made to have sufiicient mechanicalstability but require frequent readjustment and, thus, repeated checkingof the setting, because the original setting slowly changes undercontinuous vibration. Another important disadvantage of such prior artoptical installations is that any new setting upon change of productionrequires highly skilled personnel and is quite timeconsuming. Forexample, a new setting of a prior art checking apparatus typically mayrequire up to ten hours while resetting of the production plant propernormally can be done within about an hour only. Thus, the time nowrequired for change of container produc tion, be it in size or in typeof the containers, will depend essentially upon the time required forsetting the test components and, specifically, the crack-checkingapparatus.

In order to obviate these problems it has been suggested to use a systemof special support rods and pivotable clamps for mounting the testdevices, the rods and clamps being provided with scales and circulardivisions engraved thereon so that a setting once selected could berepeated or reproduced easily. Practice has shown, however, that sucharrangements, while facilitating an approximative setting, still requireadditional fine setting which again is complicated and time consuming.Also, the engraved scales of the support rods and the circular divisionsof the pivot clamps render such mounting devices quite expensive. US.Pat. No. 3,085,160 issued to Dahms in 1963 shows such a system. Modernautomated plants generally produce glass containers of standardizedshapes and dimensions and most commercial production machines have to becapable of producing a certain variety of such container types.Accordingly, it would be desirable to have a means for at leastpartially replacing prior art mounting and supporting mechanisms such asrods, rails, cross bars and clamps for supporting the testinginstallations with integrated arrangements in the form of testing headsfor fixed or preset adjustment, each testing head being suitable for usein the inspection of specific container type of specific group ofcontainers.

SUMMARY OF INVENTION Accordingly, the invention relates to acrackchecking apparatus for the inspection line of an installation orplant for producing glass containers, said apparatus comprisingconveying means to carry containers for testing in a distanced relationto a checking position where the vertical axis of said containerssubstantially coincides with a checking axis that serves as a referenceaxis, each container in said checking position being rotated at leastonce around its vertical axis, said conveying means further serving tocarry said containers from said checking position to a transportinstallation, and said apparatus further comprising at least one opticalchecking arrangement including a light emitter for directing a lightbeam onto a predetermined area of a container in said checking position,and at least one light sensor cooperating with said light emitter toreceive reflected light from said container, the apparatus beingcharacterized by a testing head with fixed positioning rods for saidoptical checking arrangement, and by supporting means suitable forremovably receiving and holding said testing head in a predeterminedposition relative to said checking axis.

Upon change of the production plant from production of one type ofcontainers to another, the crackchecking apparatus according to theinvention can be set within a couple of minutes and generally setting orresetting of the crack-checking apparatus for a change of the type ofcontainers produced can be effected within a time period shorter thanthat required for the change of the production plant proper. Anadditional advantage is that such setting or resetting of thecrackchecking apparatus can be done by unskilled or semiskilledpersonnel and without subsequent control of containers produced duringthe period of transition from one container type to the other. Accordingto the art, the containers produced during the period of transitioncannot be inspected automatically and require post-checking. As theinvention provides for complete reproducibility of a given setting ofthe testing devices, the quality of testing can be improved. Also theintegral and substantially unchangeable mounting of the testing deviceswill not be changed by strong vibrations of the plant even duringextended operational runs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 3 is a schematic plan view of thecontainer handling portion of the apparatus shown in FIG. I, includingthe transport belt.

FIG. 4 is a schematic block diagram showing the mode of operation forthe various components depicted in FIG. 3.

FIG. 5 is an elevational view of a bench set-up or jig for use inpracticing the method of fabricating an inspection head according to myinvention.

FIG. 6 is another elevational view (partly in section) of the jig ofFIG. 5.

FIG. 7 is still another elevational view of additional apparatus forfabricating an inspection head according to my invention.

DETAILED DESCRIPTION The arrangement of FIG. 1 includes a main conveyor10, made, for example, of plates or the like interconnected to form anendless belt arrangement, of a conveying installation for transportingthe containers to the various stations of an inspection line. Theparticular station shown in FIG. 1 is a crack-checking apparatusarranged alongside the conveyor 10 and comprising means for carrying thecontainers in spaced relationship to a station where each container isrotated momentarily and then returned to the conveyor 10, or rejected. Atesting head, and electronic measuring and computing installations areall supported by a frame or chassis arrangement.

The frame includes two vertical support structures or beams 11, 12 eachhaving a U-shaped cross-section and both being connected by horizontalbeams 13 and 14, the connections normally being welds. For increasedstability of the frame, the lower ends of the support beams are providedor connected with horizontal base plates 16, 17. The open ends ofU-shaped beams ll, 12 extend towards conveyor 10. Arranged within beams11, 12 are vertical helices or spindles 18 (only one spindle beingvisible in FIG. 1) carrying gear boxes 19, 21 which constitute parts ofthe conveying means. Both spindles extend through vertical beam 13 andare guided by spindle heads 22, 23. The two adjacent side walls 24, 26of U-shaped beams ll, 12 include several borings 27 arranged in pairs ofvertical series and serving to support and secure a pair of arms 28, 29in several different levels above the main conveyor. A frame portion 31further connects the adjacent sidewalls 24, 26 of the beams. Arms 28, 29serve as supporting means for a testing head (to be described more indetail below), while frame portion 31 serves to support further machineunits (also to be described more in detail below). At both ends of beamwalls 24, 26 and below beam 13 a housing 30 is mounted to receiveelectrical and electronic measuring and testing devices which cooperatewith the testing head.

Arranged above each gear box 19, 21 is a driving motor (not shown inFIG. 1) with coordinated switching devices and covered by lids 32, 33.Gear box 21 on the entry side of the apparatus supports a feed-in arm36. This arm extends towards main conveyor and carries a feed-infriction band or belt 37 which is guided by a set of rollers.Downstream, a central friction band or transport belt 38 is provided,also guided by a set of rollers mounted below gear boxes 21, 19. Thetransport belt has a generally linear active run extending between anupstream pulley 38a in the box 21 and a downstream pulley 38b in box 19.

A double-action transfer friction belt 39 is arranged between feed-infriction belt 37 and transport belt 38, while a first double-actionbrake friction belt 41 is arranged downstream of the said active run ofthe transport belt. The transport belt cooperates with two pressurerollers 42, 43 mounted on pivot arms 44, 46 respectively. These arms arecapable of pivoting independently of one another in a horizontal planeas described more in detail below. The various friction belts or bandsare not only guided by the rollers shown in FIG. 1 but additionalrollers shown in FIG. 3 of the drawings are also arranged to return,tension and drive the belts. Referring more particularly to FIG. 3, thetransport belt 38 is preferably driven continuously by a motor M andthis belt is also entrained on additional pulleys also located in themain frame of the machine. Another motor M drives the friction belts 37and 39. The belt 41 at the exit end of the main frame is driven at sucha speed as to cooperate with a belt 52, to be described, and therebydecrease the rotational speed of the container as it moves onto conveyor53. Still with reference to FIG. 3 and to the main frame of the machine,the pressure rollers 42 and 43, and more particularly the respectiveaxles or stub shafts upon which they are mounted, serve to wrap asegment of the belt 38 around a portion of the periphery of thecontainer being inspected. The downstream or second arm 44 is springbiased toward the active position for so wrapping the belt 38. Theupstream, or first arm is spring biased toward its inactive position anda solenoid device 200 is selectively operable as suggested in FIG. 4 tomove the arm 46 into its active position.

Having thus described that portion of the main frame of the machinerelating to the container handling means, the complementary unit of theconveying means will now be described. The complementary machine unit ofthe conveying means is adjustably connected with frame portion 31 toaccommodate articles of various diameter. This unit is arrangedsubstantially at the level of the above described friction belts. Itincludes an entry or feed-in guide rail 47 on the entry side and injuxtaposition to arm 36, a bottom guide plate 48 and, in the area of thecentral friction belt, a central rail 49 consisting of upstream anddownstream portions, and a central bottom plate 51 composed of severalplatelets. This unit further includes a second friction belt 52 on theexit side and juxtaposed to friction belt 41. Adjacent to central bottomplate 51 is a two-partite outfeed transfer belt arrangement 53, 54actuated by a motor (not shown). Guide rail 56 is provided above theoutfeed transfer devices such that the component belts and the guiderail are capable of conveying the tested containers back onto mainconveyor belt 10. A central or back-up wheel 57 is arranged between thetwo components or portions of central guide rail 49. Preferably, thiswheel is under spring tension and connected with a drive and brakearrangement 58. The back-up wheel 57 has an active segment which extendsbeyond the rail 49 and as so oriented said wheel cooperates with theidler rollers 42 and 43 to define the inspection station therebetween.The back-up wheel drive and brake unit 58 is operated by control meansto be described in greater detail with reference to FIG. 4. Both partsof the central guide rail as well as the guiding roller and the secondfriction band are covered in part by lid 59.

FIG. 2 shows a side elevational view of the central portion orinspection station of the crack-checking apparatus, as viewed in thedirection of arrow 61 in FIG. 1, the portions of the complementarymachine unit being omitted from this view for clarity. A container 64 issupported by central bottom plate 51 and is guided by pressure rollers42, 43 and by the back-up wheel 57 such that its vertical axissubstantially coincides with a fixed testing reference axis 66, thelatter being determined by the set-up of the checking apparatus. Thecontainer is rotated around the checking axis by means of friction belt38 substantially at the level of the containers center of gravity. As isapparent from FIG. 2, arms 44, 46 supporting pressure rollers 42, 43 aremounted on rock shafts 67, 68 which protrude from gear boxes 19, 21. Forguiding the container in the area of the container neck, a furtherguiding arrangement is provided. This includes three rollers 69, 71 and72. Rollers 69, 72 are supported by pivotable arms or levers 73, 74. Thelevers are supported on the upper ends of the rock shafts 67, 68 whichprotrude from gear boxes 19, 21. The upper end 76 of shaft 67 is shownat the top of gear box 19 in FIG. 1. The third roller 71 is supported byan intermediate member 77 pivotally mounted on a support rod 78 andcapable of being pivoted radially to the testing axis, i.e. verticallyto the plane of the drawing.

Each arm 28, 29 supports at least one two-partite clamping member 79, 81which may be tightened securely onto the corresponding arm, e.g. byscrews not shown. One arm 29 is provided with a marker 82 while thecoordinated part of clamp 81 comprises an indicator 83. With the help ofsuch marking means the clamp can be repeatedly secured at apredetermined location by shifting in the longitudinal direction of thearm, i.e. vertically to the plane of the drawing. At the upper part ofthe clamp a support plate 84 is mounted and secured, and the distancebetween clamp and plate can be adjusted by means of replaceable shimjackets or tubes 85, 86. Support plate 84 comprises at least two, andpreferably four borings, which are accurately located with respect toaxis 66. A mounting block 87, made for example by molding and setting ofduroplastic resin, is arranged below the support plate. Support bolts88, 89 are located in the boring of plate 84 and are embedded in theblock. Several support or mounting rods are embedded in the mountingblock. Rod 78 supports the third roller 71 of the guiding installationfrom the support plate 84. The two other rods 91, 92 of the embodimentshown are provided to carry a light emitter 93 and a light sensor 94. Asystem or pair consisting of a light emitter and a light sensor will beunderstood to constitute an optical checking unit. In the embodimentshown, the light emitter and the light sensor are not directly securedto the support rod. In order to arrange either light emitters or lightsensors on any rod at various distances and in various angularpositions, the free end of each rod is provided with a support 96 havinga tapered end portion 95 provided with a securing plate 97. Support rods91, 92 and exchangeable carriers are provided with a groove-and-tonguejoint arrangement 98 so that the orientation of the support rods areprecisely defined in a horizontal plane, vertical to the plane of FIG. 2of the drawings. The light emitter and light sensor are well knownoptical systems. In the embodiment shown, the light emitter receiveslight from a remote light source by means of a glass fibre bundle 99.The light sensor also is connected with a glass fibre bundle 101 tocarry any light received by the sensor to a light-sensitive element,generally referred to as a light detector.

When the testing apparatus is in operation, containers on the mainconveyor will be conveyed in the direction of arrow 102 (FIG. 1) andinterupted by entry guide rail 47, and will come in contact withfriction belt 37. The distance between the entry guide rail and thejuxtaposed friction belt corresponds substantially with the diameter ofthe container tested so that the containers, one after the other, arereceived by the friction belt and rolled on bottom plate 48 in uprightposition and along entry guide rail 47. The belt is driven at such aspeed that the containers are advanced or rolled on plate 48 at asomewhat slower speed than on the main conveyor 10. Transfer belt 39operates substantially at the same speed as the entry friction belt 37so that the containers are rolled at constant speed and in closesequence onto central bottom plate 51. Central friction belt 38 operatesat a speed greater than the entry friction belt. Therefore, thecontainers are rolled more speedily along the central guide rail 49 thanalong the entry guide rail 47 and therefore the container spacing iscaused to increase between the individual containers on the base 51.Prior to entry of a container into the inspection station, pressureroller 43 on arm 46 will be pivoted out of the path of the container, inthe direction toward the main frame of the machine so that the containerwill abut the downstream idler or roller 42.

Referring now to FIGS. 3 and 4, a series of proximity switches S S and5;; are provided in the path of each container on the base 51 as it ismoved by the belt 38 into the inspection station, and after it isreleased therefrom. Closing of switch S starts a brief time delay andtriggers a counter 204, which counter receives a clock pulse timed tothe transport belt 38, through a pulse generator 206. As the next switchS closes, counter 204 provides an input to the solenoid operator 200 forthe upstream or first idler arm causing roller 43 to move into itsactive position, and thus trapping the container 64 at the inspectionstation. Switch S also activates the back-up wheel drive portion of unit58. This unit is designed to drive the wheel 57 up to a speed ofapproximately 80 percent of the design angular rotation for theparticular container to be spun. The wheel 57 is declutchedautomatically as the container starts driving it.

A position sensor 201, associated with the first or upstream idler arm46, provides a start pulse to rotation counter 210, which counter isalso clocked through the transport belt pulse generator 206. Uponexpiration of a predetermined count set in counter 210 (corresponding toat least one complete revolution) an input is provided to the back-upwheel brake portion of unit 58, and to the control unit 202 associatedwith the second or downstream idler arm 44. Thus, the inspectedcontainer is decelerated on the side opposite the transport belt 38, androller 42 swings clear of its path allowing the container to be rolledout of the inspection station.

As explained above, back-up wheel 57 is driven during entry of acontainer into the inspection station, the direction of rotation beingopposite to the direction of operation of transport belt 38. Theperipheral speed of the central roller corresponds to about percent ofthe speed of movement of the central friction belt. As soon as thecontainer rolling along the first part of central guide rail 49 comes incontact with central roller 57 rotating in an opposite direction, themovement of the container through the transport installation, i.e. themovement of translation, will be stopped. In order to prevent reboundingof the container, the entry pressure roller 43 will be pivoted back intothe operating position shown in FIG. 3 so that the container will beguided by pressure rollers 42, 43 as well as central roller 57 androtated in place, i.e. there is no movement of translation. It will beunderstood that rollers 69, 72 which contact the container neck will bepivoted simultaneously in the same direction as pressure rollers 42, 43.

While the container is rotated at the inspection station, the areas ofthe containers to be checked or inspected for defects or cracks of thetype explained above, particularly for detecting such defects in thearea of the container outlet and the lower neck or shoulder portion,will be impinged by light from several light emitters 93. When a lightbundle 103 impinges upon a crack 104, light will be reflected, and there flected light bundle will impinge upon a light sensor 94. In order toexclude noise signals as far as possible, both the light emitter and thelight sensor are provided with an optical lens system so that theemitted or reflected light bundle will have a small diameter, and thatthe light sensor will receive light bundles of a well defined direction.Since each light emitter and corresponding light sensor will be capableof checking a limited portion or area of the container only, a pluralityof light emitters and light sensors will be required. In technicaloperation of a commercial apparatus up to twelve or more light emittersand up to twenty light sensors will be used. In order to arrange such alarge number of light emitters and light sensors in the available space(for example, they must not be in the path of the containers nor hindertheir movement), the light sources as well as the light detectors ormultipliers are arranged in a position remote from the checkingposition, e.g. within electronic control box 106. Conduction of lightfrom control box to emitter and from the light sensor to the control boxagain can be effected by means of light conductor 99, 101. While asingle optical checking arrangement (i.e. a pair of one light emitterand one light sensor) and a single control box is shown in FIG. 2 only,it is to be understood that several checking installations as well asseveral control boxes will be required for commercial operation.

Each light bundle reflected by a crack will trigger a control signal tooperate a mechanism of rejection 212 so as to eject a defectivecontainer after such container has left the inspection station. As shownin FIG. 3 the reject device 212 is preferably an air operated devicecapable of removing the defective container by blowing it off the firstof two outfeed conveyors 53 at the general location shown. Theinspection equipment described above will provide a reject signal to asignal memory device 214, which device has three stages to delayoperation of the reject unit 212 until the defective container reachesthe position for rejection. The first stage assures that the containeris fully inspected, the second stage assures that the container has leftthe inspection station and had time to move to the end of the belt 38.Finally the third stage is associated with a counter 218, which counter218 is started by the output from the same counter 216 which satisfiesstage II of signal memory 214, but which counter 218 is clocked by apulse generator 220 associated with the outfeed conveyor 53. When allthree stages of signal memory 214 have been satisfied reject unit 212 isenergized, removing the defective container from outfeed conveyor 53.

As soon as the container has completed at least one full rotation aroundits axis, exit pressure roller 42 supported by arm 44 will be pivotedout of the path of movement of the container and towards the chassisframe, while central roller 57 will be stopped simultaneously. As soonas the peripheral velocity of the central roller will be slower than thespeed of movement of central friction belt 38, the container will bemoved along the roller and transported out of the inspection station. Itwill then roll along the exit part of central guide rail 49. At the endof both the central rail and the central bottom plate the container willbe received by brake friction belts 51, 52 rotating in oppositedirections so that the rotation of the container will be braked and thecontainer with no rotational movement will be moved onto outfeedconveyor 53 arranged at the end of the conveying installation.

By way of summary, the pivoting movement of the pressure rollers 42 and43 will be controlled by switches S and S These switches are arranged inthe entry part, and another 8;, in the exit part. Acceleration andbraking of the back-up wheel will be effected electrically, and willdepend upon the pivoting movement of the pressure rollers.

In a test set-up which would be typical of commercial installation, thecrack-checking apparatus according to the invention was found capable oftesting 250 containers per minute, each container having a diameter of70 mm and a weight of about250 g. The residence time of a container atthe inspection station, (i.e. the time period required for checking) wasonly about 0.1 seconds.

In order to adapt the crack-checking apparatus for processing containersof different dimensions, the main frame of the machine including thegear boxes with attached pressure rollers as well as the rollers of theguiding installation and the friction belts, can be displaced invertical and horizontal directions.

For adjusting a testing head of the type disclosed in FIG. 2 a set-upfixture, best shown in FIGS. 5, 6, and 7, will be described. A supportplate 84a, corresponding to plate 84 in FIG. 2, will first be arrangedin the checking apparatus or in a simulating device or set-up fixture.This horizontal plate 84a includes a plurality of vertical borings 88a,88a, which are preferably arranged in line with keyways or grooves 98a,98a. That is, each boring 88a is provided with a keyway or groove whichwill receive a tongue portion 98b on each of the auxiliary support rods91a and 92a. The actual number of such auxiliary support rodscorresponding to the number of the optical checking installations andall of said rods are secured in borings 88a, 88a of the support plate84a. These auxiliary support rods 91a and 92a are provided at those endswhich are to be inserted into the borings with tongue portions 98bcapable of being inserted into the groove portions 980 therebypreserving a desired orientation of the rods. The auxiliary support rods91a and 92a can be of different lengths so as to provide for securing ofthe optical checking installations at different distances from thesupport plate 51, or from the containers to be checked. At the lower, orfree end portion of each auxiliary support rod 92a a carrier 96 issecured having a laterally displaced tapered free end 95. In order tomount and secure light emitters and light sensors in different distancesand with different inclination vis-a-vis the container to be checked,carriers of different length and of different taper can be used.Furthermore, the lower end of each auxiliary support rod also comprisesa groove portion 980 while the coordinated face of each carriercomprises a mating tongue portion as shown in FIG. 5. To set the opticalchecking installation in different alignments, carriers having tongueportions in differing arrangements can be used. When the light emittersand light sensors are optimally adjusted by means of a testcontainer setin checking position, a data sheet defining the carriers used as well astheir coordination with the auxiliary rods will be prepared. Thereafter,the carriers may be dismounted from the auxiliary support rods. Thesupport plate 84a with the auxiliary support rods then are secured inthe set-up of FIG. 6. Guiding rods 91b and 92b are inserted in exactjuxtaposition to the auxiliary support rods 91a and 92a in an auxiliarysupport plate 84b. The guiding rods will be connected to the free endsof the auxiliary support rods by unions 93a, 93a. Each union and rod endhave mating tongue and groove portions similar to the ends 98b of theauxiliary support rods. The lower, or auxiliary support plate 84b, withits coordinated guiding rods 91b and 92b then constitutes a negative ora stencil for the upper plate 84a with the auxiliary support rods 91aand 92a. Upon separation of the upper support plate 84a, with theax'xiliary support rods 91a and 92a from the auxiliary support plate 84bwith the guiding rods 91b and 92b, the free ends of the guiding rods canbe provided withthe support rods 91 and 92. The groove end portions ofthese support rods shown in FIG. 7 mate with the tongue portions of theguiding rods, and the lengths of each support rod is such that itslength, when combined with its guiding rod provides a constant length Lin FIG. 6. This arrangement for each support rod, such as 92, will thenbe mounted in a casting mold, which mold is filled, subsequently, with amolding or casting composition, preferably a duroplastic resincomposition, comprising an epoxy resin. After setting or solidificationof the casting composition and dismounting of the guiding rods from thesupport rods, the testing head 87 thus produced can be inserted into thecrack-checking apparatus, or inspection machine of FIG. 1.

Now, according to the embodiment illustrated in FIG. 1 and explainedpreviously, a testing head which includes a mounting block and supportrods can be used, after reassembling the carriers per the data sheet, tocheck containers of differing dimensions or shapes. It is possible,therefore, to permanently secure the carriers on the support rods and touse a separate testing head for each type of container. Also, it is notrequired to fix the optical testing installations in the mannerdescribed above and different means of securing light emitters and lightsensors can be used, such as securing them in a boring at the lower endof the support rods. The set-up fixture used for the preparation of themounting block can be used repeatedly.

Further, it is possible to leave the mounting block in I the mold sothat the mold 109 (FIG. 2) forms a part of the testing head. When themounting block is removed from the mold after setting or solidificationof the casting composition, the support bolts must be embedded in theblock. When the casting mold 109 is used as a part of the testing head87, the support bolts can be secured in the casting mold. By selectingborings 27 (FIG. 1) for securing of arms 28, 29 and selecting the lengthor height of the intermediary shim jackets, or tubes 85, 86, the testinghead, for example, can be secured in any required level above centralbottom plate 51 for checking of containers of different height.

I claim:

1. Container inspection apparatus for use alongside a containerconveyor, and comprising:

a. a base for supporting the containers in upright position as they aremoved along in a line and a rail against which the containers areadapted to be rolled as they are so moved;

b. means for diverting containers from the conveyor onto an upstream endof said base;

c. means for metering the containers so moving onto the base;

a continuously driven endless transport belt located at one side of saidbase, generally opposite said rail to roll the containers and advancethem at a speed greater than that permitted by said metering means tospace the containers along said base;

e. means for'rotating each container on a fixed reference axis at aninspection station, said rotating means including said transport beltand means for wrapping a segment of said belt around a portion of theperiphery of the container being inspected at said station; and

f. said means for so wrapping said belt being selectively movable intoand out of engagement with said belt to permit at least one fullrevolution of the container being inspected on said reference axis.

2. The apparatus of claim 1 further characterized by a containerengaging back-up wheel at said inspection station, which back-up wheelis located on the same side of said container line as said rail, andagainst which back-up wheel said container can be rotated about saidreference axis by said belt at said inspection station, said rail havingan active segment projecting beyond said rail.

3. The apparatus of claim 1 wherein said transport belt also extendsdownstream of said inspection station to roll the inspected containeraway from said station along said rail when said means for so wrappingsaid belt is moved out of engagement with said belt.

4. The apparatus of claim 1 further characterized by light emitter andsensor means and associated circuitry at said inspection station forgenerating a reject signal when a container being inspected does notproduce the, desired inputs to said sensor means in response to apredetermined illumination pattern from said emitter means.

5. The apparatus of claim 1 wherein said means for metering the movementof containers onto said base comprises a side belt oriented at an angleto the container conveyor and to said transport belt, said side beltbeing continuously driven at a speed less than the speed of saidtransport belt.

6. The apparatus of claim 1 wherein said means for so wrapping saidtransport belt segment comprises first and second rollers, each of whichrollers is mounted on associated first and second crank armsrespectively, and means for moving each of said arms independently ofone another.

7. The apparatus of claim 6 further characterized by first and secondcontainer sensing switches located in spaced relation along the line ofmovement of the containers being rolled into said inspection station andadapted for sequenced closing in response thereto, circuit meansresponsive to said switch closings and including motor means for movingsaid crank arm into its active position, and said circuit meansincluding as an additional input means responsive to the speed ofmovement of said transport belt so that said first roller reaches itsactive position only after a container has reached said inspectionstation.

8. The apparatus of claim 7 further characterized by a containerengaging back-up wheel at said inspection station, which back-up wheelis located on the same side of said container line as said rail, andagainst which back-up wheel said container can be rotated about saidreference axis by said belt at said inspection station, said rail havingan active segment projecting beyond said rail.

9. The apparatus of claim 8 wherein said circuit means includes meansfor selectively driving and braking said back-up wheel, said back-upwheel drive means being energized through the second container sensingswitch and being deenergized when said backup wheel braking means isenergized, said circuit further including a container revolutioncounter, and said braking means being energized after at least onerevolution of the container at said inspection station and said secondcrank am being moved to its inactive position simultaneously therewith.

10. The apparatus of claim 7 wherein said circuit means responsive tosaid sequentially closed container sensing switches comprises a counterwith a first input from said first switch, a pulse generator driven fromsaid transport belt and providing a clock pulse for said counter, saidcounter having a second input from said second switch and an output fromsaid counter for controlling said motor means for said first crank arm.

11. The apparatus of claim 3 wherein said transport belt includes anactive segment or run which follows a generally straight path parallelsaid container conveyor said transport belt active run having anupstream end adjacent said container metering means and a midportionadjacent said inspection station and a downstream end spaced beyond saidstation, and pulleys at said upstream and downstream end of said activerun.

12. The apparatus of claim 11 further characterized by a containerengaging back-up wheel at said inspection station, which back-up wheelis located on the same side of said container line as said rail, andagainst which back-up wheel said container can be rotated about saidreference axis by said belt at said inspection station, said rail havingan active segment projecting beyond said rail.

13. The apparatus of claim 12 wherein said means for metering themovement of containers onto said base comprises a side belt oriented atan angle to the container conveyor and to said transport belt, said sidebelt being continuously driven at a speed less than the speed of saidtransport belt.

14. The apparatus of claim 13 wherein said means for so wrapping saidtransport belt segment comprises first and second rollers, each of whichrollers is mounted on associated first and second crank armsrespectively, and means for moving each of said arms independently ofone another.

15. The apparatus of claim 14 wherein said base has a downstream endadjacent the downstream end of said active run of said transport belt,horizontally oriented return conveyor means downstream of said base andgenerally parallel said container conveyor, and vertically oriented exitbelts adjacent the marginal side edges of said return conveyor, eachbeing driven in a sense opposite that of the other to convert therolling motion of the inspected containers leaving said base to simpletranslatory motion.

16. The apparatus of claim 4 further characterized by supporting meansfor said light emitters and sensors at said inspection station, saidsupporting means including a molded block of plastic material supportedat a predetermined height above said base, a plurality of rods havingtheir upper ends embedded in said block in a predetermined pattern andtheir lower ends located at various predetermined distances above saidbase, a plurality of horizontally extending support members carried bythe lower ends of said rods respectively, and each of said supportmembers being oriented at a predetermined angle in its own horizontalplane, said light emitters and sensors being carried by said supportmembers in spaced relation to said rods and at predetermined angles withrespect to said rods.

17. The apparatus of claim 16 wherein said block comprises a set epoxyresin of heat and age resistant 14 composition.

18. In a glass container inspection apparatus of the type whereincontainers are advanced single file to an inspection station formomentary rotation on an axis fixed in the apparatus the improvementcomprising three independently mounted rollers defining said inspectionstation axis, at least two of said rollers being movable toward and awayfrom said axis to trap a container therebetween, and a side belt whichis engaged by said two movable rollers so that said side beltsclcctively engages the container to rotate it on said axis betweenthree rollers whenever at least one of said two movable rollers is movedtoward said axis.

19. The combination of claim 18 further characterized by said side belthaving an active run extending upstream of said inspection station andthereby serving to advance containers into said inspection station.

20. The combination of claim 19 further characterized by said side belthaving said active run extending downstream of said inspection stationto move containers out of said inspection station.

21. The combination of claim 19 further characterized by a glide railopposite said active run with respect to the path of movement of thecontainers being advanced to roll these containers into said inspectionstation.

22. The combination of claim 20 further characterized by a guide railopposite said active run with respect to the path of movement of thecontainers being advanced to roll these containers into said inspectionstation.

23. The combination of claim 22 wherein said third roller extendsinwardly past said rail so that an active peripheral portion engages thecontainer at said inspection station.

24. The combination of claim 23 wherein said third roller is selectivelydriven and braked, and wherein it is driven to increase the angularvelocity of the rolling container entering the inspection station andbraked to facilitate removal of the container from said station by saidside belt.

25. The combination of claim 18 wherein said rollers are not drivenduring the spinning of said container during inspection, and arms forsaid at least two rollers, said side belt being wrapped around a segmentof the container during inspection by said arms.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,848,742 Dated November 19, 1974 Inventor(s) Willy Krenmayr It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Col. 1, line 32, "msut" should be must.

Col 2, line 66, "for change" should be -for a change.

Col. 8, line 61, "conductor" should be -conductors-.

Col. 10, line 49, "axxiliary" should be -auxiliary-.

Signed and Scaled this A trest:

RUTH C. MASON C. MARS Allesling Officer DANN mnmissium'r nj'larwns andTradvmarks

1. Container inspection apparatus for use alongside a containerconveyor, and comprising: a. a base for supporting the containers inupright position as they are moved along in a line and a rail againstwhich the containers are adapted to be rolled as they are so moved; b.means for diverting containers from the conveyor onto an upstream end ofsaid base; c. means for metering the containers so moving onto the base;d. a continuously driven endless transport belt located at one side ofsaid base, generally opposite said rail to roll the containers andadvance them at a speed greater than that permitted by said meteringmeans to space the containers along said base; e. means for rotatingeach container on a fixed reference axis at an inspection station, saidrotating means including said transport belt and means for wrapping asegment of said belt around a portion of the periphery of the containerbeing inspected at said station; and f. said means for so wrapping saidbelt being selectively movable into and out of engagement with said beltto permit at least one full revolution of the container being inspectedon said reference axis.
 2. The apparatus of claim 1 furthercharacterized by a container engaging back-up wheel at said inspectionstation, which back-up wheel is located on the same side of saidcontainer line as said rail, and against which back-up wheel saidcontainer can be rotated about said reference axis by said belt at saidinspection station, said rail having an active segment projecting beyondsaid rail.
 3. THe apparatus of claim 1 wherein said transport belt alsoextends downstream of said inspection station to roll the inspectedcontainer away from said station along said rail when said means for sowrapping said belt is moved out of engagement with said belt.
 4. Theapparatus of claim 1 further characterized by light emitter and sensormeans and associated circuitry at said inspection station for generatinga reject signal when a container being inspected does not produce thedesired inputs to said sensor means in response to a predeterminedillumination pattern from said emitter means.
 5. The apparatus of claim1 wherein said means for metering the movement of containers onto saidbase comprises a side belt oriented at an angle to the containerconveyor and to said transport belt, said side belt being continuouslydriven at a speed less than the speed of said transport belt.
 6. Theapparatus of claim 1 wherein said means for so wrapping said transportbelt segment comprises first and second rollers, each of which rollersis mounted on associated first and second crank arms respectively, andmeans for moving each of said arms independently of one another.
 7. Theapparatus of claim 6 further characterized by first and second containersensing switches located in spaced relation along the line of movementof the containers being rolled into said inspection station and adaptedfor sequenced closing in response thereto, circuit means responsive tosaid switch closings and including motor means for moving said crank arminto its active position, and said circuit means including as anadditional input means responsive to the speed of movement of saidtransport belt so that said first roller reaches its active positiononly after a container has reached said inspection station.
 8. Theapparatus of claim 7 further characterized by a container engagingback-up wheel at said inspection station, which back-up wheel is locatedon the same side of said container line as said rail, and against whichback-up wheel said container can be rotated about said reference axis bysaid belt at said inspection station, said rail having an active segmentprojecting beyond said rail.
 9. The apparatus of claim 8 wherein saidcircuit means includes means for selectively driving and braking saidback-up wheel, said back-up wheel drive means being energized throughthe second container sensing switch and being deenergized when saidback-up wheel braking means is energized, said circuit further includinga container revolution counter, and said braking means being energizedafter at least one revolution of the container at said inspectionstation and said second crank arm being moved to its inactive positionsimultaneously therewith.
 10. The apparatus of claim 7 wherein saidcircuit means responsive to said sequentially closed container sensingswitches comprises a counter with a first input from said first switch,a pulse generator driven from said transport belt and providing a clockpulse for said counter, said counter having a second input from saidsecond switch and an output from said counter for controlling said motormeans for said first crank arm.
 11. The apparatus of claim 3 whereinsaid transport belt includes an active segment or run which follows agenerally straight path parallel said container conveyor said transportbelt active run having an upstream end adjacent said container meteringmeans and a mid-portion adjacent said inspection station and adownstream end spaced beyond said station, and pulleys at said upstreamand downstream end of said active run.
 12. The apparatus of claim 11further characterized by a container engaging back-up wheel at saidinspection station, which back-up wheel is located on the same side ofsaid container line as said rail, and against which back-up wheel saidcontainer can be rotated about said reference axis by said belt at saidinspection station, said rail having an active segment projecting beyondsaid rail.
 13. The apparatus of clAim 12 wherein said means for meteringthe movement of containers onto said base comprises a side belt orientedat an angle to the container conveyor and to said transport belt, saidside belt being continuously driven at a speed less than the speed ofsaid transport belt.
 14. The apparatus of claim 13 wherein said meansfor so wrapping said transport belt segment comprises first and secondrollers, each of which rollers is mounted on associated first and secondcrank arms respectively, and means for moving each of said armsindependently of one another.
 15. The apparatus of claim 14 wherein saidbase has a downstream end adjacent the downstream end of said active runof said transport belt, horizontally oriented return conveyor meansdownstream of said base and generally parallel said container conveyor,and vertically oriented exit belts adjacent the marginal side edges ofsaid return conveyor, each being driven in a sense opposite that of theother to convert the rolling motion of the inspected containers leavingsaid base to simple translatory motion.
 16. The apparatus of claim 4further characterized by supporting means for said light emitters andsensors at said inspection station, said supporting means including amolded block of plastic material supported at a predetermined heightabove said base, a plurality of rods having their upper ends embedded insaid block in a predetermined pattern and their lower ends located atvarious predetermined distances above said base, a plurality ofhorizontally extending support members carried by the lower ends of saidrods respectively, and each of said support members being oriented at apredetermined angle in its own horizontal plane, said light emitters andsensors being carried by said support members in spaced relation to saidrods and at predetermined angles with respect to said rods.
 17. Theapparatus of claim 16 wherein said block comprises a set epoxy resin ofheat and age resistant composition.
 18. In a glass container inspectionapparatus of the type wherein containers are advanced single file to aninspection station for momentary rotation on an axis fixed in theapparatus the improvement comprising three independently mounted rollersdefining said inspection station axis, at least two of said rollersbeing movable toward and away from said axis to trap a containertherebetween, and a side belt which is engaged by said two movablerollers so that said side belt selectively engages the container torotate it on said axis between three rollers whenever at least one ofsaid two movable rollers is moved toward said axis.
 19. The combinationof claim 18 further characterized by said side belt having an active runextending upstream of said inspection station and thereby serving toadvance containers into said inspection station.
 20. The combination ofclaim 19 further characterized by said side belt having said active runextending downstream of said inspection station to move containers outof said inspection station.
 21. The combination of claim 19 furthercharacterized by a guide rail opposite said active run with respect tothe path of movement of the containers being advanced to roll thesecontainers into said inspection station.
 22. The combination of claim 20further characterized by a guide rail opposite said active run withrespect to the path of movement of the containers being advanced to rollthese containers into said inspection station.
 23. The combination ofclaim 22 wherein said third roller extends inwardly past said rail sothat an active peripheral portion engages the container at saidinspection station.
 24. The combination of claim 23 wherein said thirdroller is selectively driven and braked, and wherein it is driven toincrease the angular velocity of the rolling container entering theinspection station and braked to facilitate removal of the containerfrom said station by said side belt.
 25. The combination of claim 18wherein said rollers are not dRiven during the spinning of saidcontainer during inspection, and arms for said at least two rollers,said side belt being wrapped around a segment of the container duringinspection by said arms.